CASABLANCA, Morocco (AP) _ Two brothers strapped with explosives blew themselves up near an American cultural center Saturday, and police arrested another three suspects _ including one wearing an explosives belt _ hours later, an official said.

The attacks came just days after three suspected militants blew themselves up as they were cornered by police in Casablanca, and al-Qaida claimed suicide car bombings in neighboring Algeria that killed 33 people. The attacks have stoked new fears of Islamic terrorism in North Africa _ especially in Morocco, long known for its stability.

The Moroccan and Algerian governments have not addressed an al-Qaida link or inspiration in the bombings earlier this week. Both countries have allied themselves with the United States in its fight against terrorism.

Saturday's two bombers detonated their explosives in the middle of a boulevard that runs behind the American Language Center, killing themselves and wounding a woman, the official said, adding that the three suspects were arrested in the neighborhood, which is dotted with high-rises, hotels and diplomatic missions, including the U.S. consulate.

After the arrests, another explosives belt was found beside an upscale hotel in the same neighborhood struck by the bombings, the Interior Ministry official said on condition of anonymity, citing ministry policy.

The official said the explosives linked the bombers with three men who blew themselves up in Casablanca on Tuesday after being cornered by police. A police sniper shot and killed a fourth man who authorities said appeared to be preparing to detonate a bomb.

The official MAP news agency reported, meanwhile, that police had arrested the leader of a group responsible for the Tuesday suicide bombings and another last month in a cybercafe in Casablanca, Morocco's largest city.

It did not identify the suspect or say when the arrest took place. The agency said hideouts where explosive devices were put together also had been uncovered, along with identities of members of the group now being sought.

The bombers were identified as Mohamed Maha, who was born in 1975 and had no previous record; and his brother, Omar Maha, who was born in 1984 and wanted in the earlier explosions.

On Wednesday, 33 people were killed and more than 200 were injured in al-Qaida-claimed suicide car bombings in neighboring Algeria that targeted the prime minister's office and a police station.

The U.S. Embassy warned of possible new attacks in Algiers on Saturday. In a statement, it said attacks could strike near the central post office and the ENTV national television headquarters. It did not cite a source for its information.

Algerian authorities have identified one of Wednesday's three reported suicide bombers who drove the cars laden with explosives, state radio and television reported.

The French-language daily Liberte identified the bomber as 23-year-old Bilal Oudina, who has been jailed three times for crimes linked to drug trafficking. It did not cite sources for its information. The paper said he began to pray and frequent Islamist circles six months ago and disappeared from his neighborhood three months ago.

Moroccan investigators have not uncovered links between the Casablanca and Algiers bombings, but Interior Minister Chakib Benmoussa has said ``we don't rule it out.''

Al-Qaida in Islamic North Africa claimed responsibility for the Algeria attacks, posting pictures, names and details about the bombers on an Islamic Web site known as a clearing house for extremist groups' material. The site said the man who attacked the prime minister's office, identified as Mouaz bin Jabl, used 1,500 pounds of explosives. Last month, a suicide attack at a cybercafe in Casablanca killed the bomber and injured four others.

The Muslim kingdom of Morocco has long been known for its stability despite the violence in neighboring Algeria. But in May 2003, five suicide bombings around Casablanca killed 45 people, including a dozen bombers.

Authorities launched an unprecedented crackdown on suspected militants, arresting thousands of people, including some accused of working with al-Qaida and its affiliates to plot attacks in Morocco and abroad.